• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* GLIB - Library of useful routines for C programming
2  * Copyright (C) 1995-1997, 1999  Peter Mattis, Red Hat, Inc.
3  *
4  * This library is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2 of the License, or (at your option) any later version.
8  *
9  * This library is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with this library; if not, write to the
16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17  * Boston, MA 02111-1307, USA.
18  */
19 
20 #include "config.h"
21 
22 #include <string.h>
23 
24 #include "gpattern.h"
25 
26 #include "gmacros.h"
27 #include "gmessages.h"
28 #include "gmem.h"
29 #include "gunicode.h"
30 #include "gutils.h"
31 #include "galias.h"
32 
33 /* keep enum and structure of gpattern.c and patterntest.c in sync */
34 typedef enum
35 {
36   G_MATCH_ALL,       /* "*A?A*" */
37   G_MATCH_ALL_TAIL,  /* "*A?AA" */
38   G_MATCH_HEAD,      /* "AAAA*" */
39   G_MATCH_TAIL,      /* "*AAAA" */
40   G_MATCH_EXACT,     /* "AAAAA" */
41   G_MATCH_LAST
42 } GMatchType;
43 
44 struct _GPatternSpec
45 {
46   GMatchType match_type;
47   guint      pattern_length;
48   guint      min_length;
49   guint      max_length;
50   gchar     *pattern;
51 };
52 
53 
54 /* --- functions --- */
55 static inline gboolean
g_pattern_ph_match(const gchar * match_pattern,const gchar * match_string,gboolean * wildcard_reached_p)56 g_pattern_ph_match (const gchar *match_pattern,
57 		    const gchar *match_string,
58 		    gboolean    *wildcard_reached_p)
59 {
60   register const gchar *pattern, *string;
61   register gchar ch;
62 
63   pattern = match_pattern;
64   string = match_string;
65 
66   ch = *pattern;
67   pattern++;
68   while (ch)
69     {
70       switch (ch)
71 	{
72 	case '?':
73 	  if (!*string)
74 	    return FALSE;
75 	  string = g_utf8_next_char (string);
76 	  break;
77 
78 	case '*':
79 	  *wildcard_reached_p = TRUE;
80 	  do
81 	    {
82 	      ch = *pattern;
83 	      pattern++;
84 	      if (ch == '?')
85 		{
86 		  if (!*string)
87 		    return FALSE;
88 		  string = g_utf8_next_char (string);
89 		}
90 	    }
91 	  while (ch == '*' || ch == '?');
92 	  if (!ch)
93 	    return TRUE;
94 	  do
95 	    {
96               gboolean next_wildcard_reached = FALSE;
97 	      while (ch != *string)
98 		{
99 		  if (!*string)
100 		    return FALSE;
101 		  string = g_utf8_next_char (string);
102 		}
103 	      string++;
104 	      if (g_pattern_ph_match (pattern, string, &next_wildcard_reached))
105 		return TRUE;
106               if (next_wildcard_reached)
107                 /* the forthcoming pattern substring up to the next wildcard has
108                  * been matched, but a mismatch occoured for the rest of the
109                  * pattern, following the next wildcard.
110                  * there's no need to advance the current match position any
111                  * further if the rest pattern will not match.
112                  */
113 		return FALSE;
114 	    }
115 	  while (*string);
116 	  break;
117 
118 	default:
119 	  if (ch == *string)
120 	    string++;
121 	  else
122 	    return FALSE;
123 	  break;
124 	}
125 
126       ch = *pattern;
127       pattern++;
128     }
129 
130   return *string == 0;
131 }
132 
133 gboolean
g_pattern_match(GPatternSpec * pspec,guint string_length,const gchar * string,const gchar * string_reversed)134 g_pattern_match (GPatternSpec *pspec,
135 		 guint         string_length,
136 		 const gchar  *string,
137 		 const gchar  *string_reversed)
138 {
139   g_return_val_if_fail (pspec != NULL, FALSE);
140   g_return_val_if_fail (string != NULL, FALSE);
141 
142   if (string_length < pspec->min_length ||
143       string_length > pspec->max_length)
144     return FALSE;
145 
146   switch (pspec->match_type)
147     {
148       gboolean dummy;
149     case G_MATCH_ALL:
150       return g_pattern_ph_match (pspec->pattern, string, &dummy);
151     case G_MATCH_ALL_TAIL:
152       if (string_reversed)
153 	return g_pattern_ph_match (pspec->pattern, string_reversed, &dummy);
154       else
155 	{
156           gboolean result;
157           gchar *tmp;
158 	  tmp = g_utf8_strreverse (string, string_length);
159 	  result = g_pattern_ph_match (pspec->pattern, tmp, &dummy);
160 	  g_free (tmp);
161 	  return result;
162 	}
163     case G_MATCH_HEAD:
164       if (pspec->pattern_length == string_length)
165 	return strcmp (pspec->pattern, string) == 0;
166       else if (pspec->pattern_length)
167 	return strncmp (pspec->pattern, string, pspec->pattern_length) == 0;
168       else
169 	return TRUE;
170     case G_MATCH_TAIL:
171       if (pspec->pattern_length)
172         return strcmp (pspec->pattern, string + (string_length - pspec->pattern_length)) == 0;
173       else
174 	return TRUE;
175     case G_MATCH_EXACT:
176       if (pspec->pattern_length != string_length)
177         return FALSE;
178       else
179         return strcmp (pspec->pattern, string) == 0;
180     default:
181       g_return_val_if_fail (pspec->match_type < G_MATCH_LAST, FALSE);
182       return FALSE;
183     }
184 }
185 
186 GPatternSpec*
g_pattern_spec_new(const gchar * pattern)187 g_pattern_spec_new (const gchar *pattern)
188 {
189   GPatternSpec *pspec;
190   gboolean seen_joker = FALSE, seen_wildcard = FALSE, more_wildcards = FALSE;
191   gint hw_pos = -1, tw_pos = -1, hj_pos = -1, tj_pos = -1;
192   gboolean follows_wildcard = FALSE;
193   guint pending_jokers = 0;
194   const gchar *s;
195   gchar *d;
196   guint i;
197 
198   g_return_val_if_fail (pattern != NULL, NULL);
199 
200   /* canonicalize pattern and collect necessary stats */
201   pspec = g_new (GPatternSpec, 1);
202   pspec->pattern_length = strlen (pattern);
203   pspec->min_length = 0;
204   pspec->max_length = 0;
205   pspec->pattern = g_new (gchar, pspec->pattern_length + 1);
206   d = pspec->pattern;
207   for (i = 0, s = pattern; *s != 0; s++)
208     {
209       switch (*s)
210 	{
211 	case '*':
212 	  if (follows_wildcard)	/* compress multiple wildcards */
213 	    {
214 	      pspec->pattern_length--;
215 	      continue;
216 	    }
217 	  follows_wildcard = TRUE;
218 	  if (hw_pos < 0)
219 	    hw_pos = i;
220 	  tw_pos = i;
221 	  break;
222 	case '?':
223 	  pending_jokers++;
224 	  pspec->min_length++;
225 	  pspec->max_length += 4; /* maximum UTF-8 character length */
226 	  continue;
227 	default:
228 	  for (; pending_jokers; pending_jokers--, i++) {
229 	    *d++ = '?';
230   	    if (hj_pos < 0)
231 	     hj_pos = i;
232 	    tj_pos = i;
233 	  }
234 	  follows_wildcard = FALSE;
235 	  pspec->min_length++;
236 	  pspec->max_length++;
237 	  break;
238 	}
239       *d++ = *s;
240       i++;
241     }
242   for (; pending_jokers; pending_jokers--) {
243     *d++ = '?';
244     if (hj_pos < 0)
245       hj_pos = i;
246     tj_pos = i;
247   }
248   *d++ = 0;
249   seen_joker = hj_pos >= 0;
250   seen_wildcard = hw_pos >= 0;
251   more_wildcards = seen_wildcard && hw_pos != tw_pos;
252   if (seen_wildcard)
253     pspec->max_length = G_MAXUINT;
254 
255   /* special case sole head/tail wildcard or exact matches */
256   if (!seen_joker && !more_wildcards)
257     {
258       if (pspec->pattern[0] == '*')
259 	{
260 	  pspec->match_type = G_MATCH_TAIL;
261           memmove (pspec->pattern, pspec->pattern + 1, --pspec->pattern_length);
262 	  pspec->pattern[pspec->pattern_length] = 0;
263 	  return pspec;
264 	}
265       if (pspec->pattern_length > 0 &&
266 	  pspec->pattern[pspec->pattern_length - 1] == '*')
267 	{
268 	  pspec->match_type = G_MATCH_HEAD;
269 	  pspec->pattern[--pspec->pattern_length] = 0;
270 	  return pspec;
271 	}
272       if (!seen_wildcard)
273 	{
274 	  pspec->match_type = G_MATCH_EXACT;
275 	  return pspec;
276 	}
277     }
278 
279   /* now just need to distinguish between head or tail match start */
280   tw_pos = pspec->pattern_length - 1 - tw_pos;	/* last pos to tail distance */
281   tj_pos = pspec->pattern_length - 1 - tj_pos;	/* last pos to tail distance */
282   if (seen_wildcard)
283     pspec->match_type = tw_pos > hw_pos ? G_MATCH_ALL_TAIL : G_MATCH_ALL;
284   else /* seen_joker */
285     pspec->match_type = tj_pos > hj_pos ? G_MATCH_ALL_TAIL : G_MATCH_ALL;
286   if (pspec->match_type == G_MATCH_ALL_TAIL) {
287     gchar *tmp = pspec->pattern;
288     pspec->pattern = g_utf8_strreverse (pspec->pattern, pspec->pattern_length);
289     g_free (tmp);
290   }
291   return pspec;
292 }
293 
294 void
g_pattern_spec_free(GPatternSpec * pspec)295 g_pattern_spec_free (GPatternSpec *pspec)
296 {
297   g_return_if_fail (pspec != NULL);
298 
299   g_free (pspec->pattern);
300   g_free (pspec);
301 }
302 
303 gboolean
g_pattern_spec_equal(GPatternSpec * pspec1,GPatternSpec * pspec2)304 g_pattern_spec_equal (GPatternSpec *pspec1,
305 		      GPatternSpec *pspec2)
306 {
307   g_return_val_if_fail (pspec1 != NULL, FALSE);
308   g_return_val_if_fail (pspec2 != NULL, FALSE);
309 
310   return (pspec1->pattern_length == pspec2->pattern_length &&
311 	  pspec1->match_type == pspec2->match_type &&
312 	  strcmp (pspec1->pattern, pspec2->pattern) == 0);
313 }
314 
315 gboolean
g_pattern_match_string(GPatternSpec * pspec,const gchar * string)316 g_pattern_match_string (GPatternSpec *pspec,
317 			const gchar  *string)
318 {
319   g_return_val_if_fail (pspec != NULL, FALSE);
320   g_return_val_if_fail (string != NULL, FALSE);
321 
322   return g_pattern_match (pspec, strlen (string), string, NULL);
323 }
324 
325 gboolean
g_pattern_match_simple(const gchar * pattern,const gchar * string)326 g_pattern_match_simple (const gchar *pattern,
327 			const gchar *string)
328 {
329   GPatternSpec *pspec;
330   gboolean ergo;
331 
332   g_return_val_if_fail (pattern != NULL, FALSE);
333   g_return_val_if_fail (string != NULL, FALSE);
334 
335   pspec = g_pattern_spec_new (pattern);
336   ergo = g_pattern_match (pspec, strlen (string), string, NULL);
337   g_pattern_spec_free (pspec);
338 
339   return ergo;
340 }
341 
342 #define __G_PATTERN_C__
343 #include "galiasdef.c"
344